Winch



J. J. Low 2,103,541

WINCH Filed Dec. 18, 1935 4 Sheets-Sheet 1 Dec. 28, 1937.

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/NvENTo/a A .u JOHN J. Low

Arme/VE J. J. LOW

WINCH Filed Dec. -l8, 1935 Dec. 28, 1937.

4 Sheets-Sheet 2 w v /N VENTO/2 JOHN J. Low

ATTORNEY Dec. 28, 1937. J. Low 2,103,541

WINCH Filed Dec. 18, 1935 4 Sheets-Sheet 5 ll-llll es l* We@ n Raw r. @Umfwww fa BYD J. J. .Low 2,103,541

WINCH Filed Deo. 18, 1955 4 Sheets-Sheet 4 Dec. 28, 1937.

A TTOENE Y DH T 1 8mm Patented Dec. 2s, 1937 l 2,103,541

` UNITED s'l'lirlssl PATENT OFFICE WINCH John J. Low, Los Angeles, Calif., assigner to Kay-Brunner Steel Products, Ine., a corporation of Delaware Application December 1s, 193s, serial No. $5,036 9 claims. (o1. as-185) My invention relates to 4Winches for hoisting Fig. 2 is a view similar to Fig. lbut without and pulling devices positioned at a distance Vthe upper drum unit. thereto and capable of operation by cables. It Figs. 3 and 4 are enlarged sectional views taken has particular reference, although not neceson the lines 3-3 and 4--4 of Fig. 1.

5 sarily, to winches adapted for attachment to Fig. 5 is a sectional View taken on the line 5 tractors to be carried and operated thereby for 54-5 of Fig.'3. actuating excavating devices of roadway excavat- Fig. 6 is an enlarged Vertical Sectional View ing machines towed by the tractors, and to pertaken 0n the line 6 5 0f Fig 1 mit complete control of the Winches by the op- Fig. 7 is anvenlarged view showing the winch i erators of the tractors. in front elevation removed from the tractor and 10 It is a purpose 0f my invention to provide a with the support attaching bolts in section.

winch embodying a sheave and cable system by Figs. 8 and 9 are vertical sectional views taken which the various devices to be actuated by the 0n the lines 8-8 and 9 9 of Fig. 6. cables can be individually operated and a fair Fig. 10 is a vertical sectional View taken on the l5 lead from the winch to each device constantly line Ill-IIJ of Fig- 7. 15 maintained irrespective of the angular position of Fig. 11 is a semi-diagrammatic view Showing the winchwith respect to the device. in' perspective the driving mechanism for the `Another purpose of my invention is the pro winch drums and a portion of the power take-off vision of a winch having a driving mechanism inmechanism.

D cluding a power take-oil mechanism which perl Fig. 12.is an enlarged seCtiOnal View taken 0n 20 mits the winch to be applied to and operated by `the line l2-l2 of Fig. l.

any conventional form of tractor, and irrespective Fg- 13 iS a detail perspective View Showing the `of the direction and rotational speed of the transattaching support by which the winch is semission shaft of the tractor, so that the rotational cured on the tractor. speed of the winch drums can be made constant The winch as herein illustrated comprises a to linearly move the cables at -such a predeterlower housing H and an upper housing H1 supermned speed as to insure,l safe operation of those imposed on the former. As the two housings are ydevices adapted to be actuated by the cables. identical in construction and the elements con- Another purpose of my invention is the protained therein the same, only the lower housing 3f, vision of a support for a winch bywhich the and its elements will be specifically described, but 30 winch can be 'attached to and rigidly supported on like numerals bearing the exponent a have been any conventional form of tractor and with the employed on the drawings to designate correwinch driving mechanism sustained in proper -sponding parts of the upper housing and the eleoperative relationship to the transmission shaft ments contained therein. 7, of the tractor. 'I'he'lower housing is made up of two end sec- 35 Another purpose of my invention is the protions l5 and i6 and an intermediate section Il. vision of a clutch and brake mechanism which Each end section I5 or I6 is made in two parts, permits the positive driving of, the absolute free as best shown in Fig. 6, and the outer part of rotation of, and the secure locking of the winch each section for the lower housing is secured to 4') drums when and as required. the corresponding part of the same section of the 40 Another purpose of my invention is the proupper housing by the provision of flanges I8 on visionof a winch having two drum units and a the sections through which bolts i9 extend. single driving mechanism therefor so correlated At the front or tractor side of the housings to the drums as to permit the winch to be used the three sections are secured in definite spaced 4; as a single or double drum unit and to allow such relation to each otherl by two angle bars 20 and 45 optional use on a tractor as conditions Amay e- 2| and a at bar 22. While at the rear side the qlllesections are similarly secured by Ithree T-bars 23 I will describe only one form of winch embodyarranged one above the other. Thus it becomes ing my invention, and will then point out the apparent that the several bars constitutea frame 5o novel features thereof in claims. which rigidly secures the several sections of each 50 In the accompanying drawings: housing together. The frame is supplemented Fig. 1 is a View showing in side elevation one by shafts, to be described hereinafter, which lend form of winch embodying my invention in apsuch additional rigidity to the frame as to proplied position on the rear end of a conventional duce housing structures of the requisite strength.. form of tractor. Each intermediate housing section4 I1 is formed 55 With a web 24 (Fig. 6) having a central hub 25 through which extends a shaft 26. Each shaft is enlarged where it extends through the hub, and at this point it is keyed to the hub to prevent rotation thereof. Two winch drums 21 and 28 are rotatably mounted on the shaft 26 by roller bearings 29 and 30, respectively. There are two such bearings for each drum contained in collars 3| and 32, respectively, formed integral with internal webs 34 and 35, respectively, of the drum. The inner bearings are retained in place by the hub 25, and the outer bearings by nuts 36-36. This arrangement permits of either drum to be removed or applied lengthwise of the shaft through the respective end of the housing.

Each winch drum 21 or 28 is provided at its outer end with two annuli 31 and 38 the confronting peripheries of which are shaped to provide a double face female clutch member. A male cone 39 having faces corresponding to those of the female member, is movable to engage and disengage the female member. This male cone is secured to a gearl 40 by cap screws 4I, and the gear in turn has an integral hub 42 which is rotatable on a sleeve 43 between collars 44 and 45. The collar 44 is threaded on the sleeve, while the collar 45 is formed integral with the sleeve and shaped to receive and support a ball bearing 46.

At the inner side of the collar 45 the sleeve 43 is splined to the shaft 26 by a feather 41 so that the sleeve is free to slide on the shaft but cannot rotate relative thereto. To the outer side of the collar 45 the sleeve has a threaded connection with an actuating sleeve 48 rotatable in and projecting from a collared opening 49 in the housing section I5 or I6. The sleeve 48 is rotatable on rings 50 secured on the shaft 26 by nuts 5|, and clamped to the sleeve is a split collar 52 on one end of an arm 53.

From the preceding description, it will be clear that the male cone 39 of the double cone clutch is operable to engage or disengage the winch drum to connect or disconnect the gear 40 thereto by rotation of the sleeve 48 in one direction or the other by operation of the arm 53. Thus the sleeve 43 is moved outward or inward on the shaft 26 to effect the requisite lateral movement of the gear 40 necessary to actuate the male cone. In 'this manner the clutch is operable to effect a driving connection between the gear and the drum. Aside from the structural simplicity of this clutch its operation is rendered positive by reason of the mounting of the gear hub 42 between the collars 44 and 45 to insure positive movement of the gear with shifting of the sleeve .43 so that the male member of the clutch will be moved completely .out of or into engagement with the female member. Thus is eliminated the possibility of the clutch dragging whenin disengaged position.

Manifestly, the two their appurtenances constitute one winch unit, and the upper drums 21 and 28a and their appurtenances constitue another winch unit. The gears 40 are adapted to be driven positively by a suitable mechanism to be described hereinafter. The upper gears 40 mesh with the lower gears to be drivenby the latter and to effect operation of the upper drums 'when the clutches therefor are` engaged. Obviously, the width of the gear teeth of all the gears is such as to maintain the gears in mesh irrespective of the lateral movements thereof necessary to the operation of the clutches.

As there is one .actuating arm 53 for each lower drums 21 and 28 and clutch, there is provided also one operating lever 54 for each arm. This winch being particularly adaptable to tractors for control by the operator of the tractor, each lever is mounted and shaped to extend upwardly and forwardly from the front side of the winch to provide an elongated handle 55 which is positioned at one side of the drivers seat, as shown in Fig. l. As best shown in Fig.,7, each pair of levers is fulcrumed on the fiat bar 22 by a bolt 56, and the short arm 51 of the lever is operatively connected to the respective arm 53 by a link 58.

The operating levers 54 and 54a, in addition to providing means for operating the clutches, provide means for actuating external contracting brakes, one for each winch drum to secure the latter against rotation at the will of the operator. The four brakes are identical in construction, only the bands and their operating mechanisms for the upper brakes are reversely arranged with respect to those of the lower brakes.

As best shown in Figs.` 6 and 9, the annulus 31 of one winch drum has an outer periphery 59 concentric of the drum axis which constitutes a brake drum to be engaged by a brake band 60. One end of this band is anchored to a bolt 6|, and the other end operatively connected to the short arm of a bell-crank lever 62 fulcrumed on the housing as at 63. A spring 64 connected to the housing by a hook 65 and to the lever 52 by'an eye bolt 66, serves to yieldably urge the lever to a position in which the band embraces the drum to effect a brake application. By means of a cam 61 rotatably supported in a bracket 68 secured to the lower angle bar 20 (Fig. 1), the brake lever 62 can be actuated against the action of the spring v64 to effect a brake release of the band with respect to the drum. As the winch drum is adapted when paying out a cable wound thereon, to rotate in a clockwise direction as when viewed in Fig. 9, the band 60, by reason of its mounting, will be actuated by such drum rotation to grip the drum and effect a brake application. In this manner the brake is rendered self energizing.

The cam 61 for the brake lever is operable to effect a brake release by the corresponding clutch arm 53, and it is connected thereto by a lost-motion connector C and a link 69. The connector is shown in Figs. 3 and 4 as comprising a pair of clevises 10 and 1I, one connected to the link 69 by a pin 12, and the other connected to the arm 53 by a pin 13. Sleeves 14 and 15 are formed on the respective, clevises 10 and 1I, and a rod 16 is movable in the sleeve 14 and provided with a retaining head 11. The other rod end is threaded in the sleeve 15 and adjustably retained therein by a nut 18.

Similarly, the clutch arm 533L for each of the upper clutches is connected to its cam 61n by a lost-motion connector C1 identical in construction to the connector C except the head 11 is dispensed with and the plain end of the rod 16a is adapted to abut a cross web 19 as it\is moved upwardly.

In constructing the connectors C and C1 to provide lost-motion between the clevises, limited movement upwardly of the clutch arms 53 and 53a from the neutral position is permitted beforethe cams 61 and 61 are actuated to effect release of the brakes. In this manner the necessity of fine adjustments of the parts concerned, is eliminated and the operator is given suilicient latitude in operation of the levers 54 and 54 to effect complete Athat of the lower drums.

engagement or disengagement of the clutches before the brakes are released or applied.

In the operation of any one clutch andthe companion brake, the arm 53 normally occupies a neutral position in which the clutch is released and the brake applied by the spring 84, thus securing the winch drum against rotation. .By moving the arm 53 downward or in a clockwise direction as when seen in Fig. 1, the clutch is engaged to drive the drum. Manifestly, the upper drums are driven in the opposite direction from Such drum rotation, in each instance, automatically releases the brake against the action of the spring so that the drum is free to be driven. When the arm 53 is elevated, that is, rotatedv counter-clockwisefrom the neutral position, the clutch remains diseni gaged but the brake is released by operation of the cam 61 so that a cable wound on the drum can be unwound therefrom as required.

Referring now to Figs. 1 and 10 the winch `drums 21 and 21, as well as the drums 28 and 28awhich are not visible in these gures, have cables 19 and 19a, respectively, wound reversely thereon. For supporting these cables so that as extended from the drums rearwardly of the winch housings they will at all times individually maintain a fair lead with respect to any mechanism or devices which they are -pulling or hoisting, and to cause the cables to be properly wound on the drums, sheave systems are provided.

The sheave system for each pair of cables 19 and 19a comprises two lowersheaves 88 and 8| and two upper sheaves 882L and 8in. As the arrangement and supports for one pair of sheaves are identical to those for the other, with the single exception of one being inverted with re- -spect to the other, a description of one will sufiice for both. Like numerals bearing the exponent "a are employed on the dra'wings to designate corresponding parts of the supports for the upper sheaves. A'

The lower sheave 88 is rotatably mounted in a housing 82 which is formed integral with and disposed laterally of a support 83. This support is elongated and tubular and it is rotatably supported at its ends in bearings 84 and 85. 'Ihe upper bearing 84 surrounds a hub 85 secured within the horizontal web of the lower'm'ost T-bar 23, while the lower bearing 85 surrounds a solid hub 81 secured in a U-shaped bracket 88 bolted to and depending from the same bar 23. A 'I'he upper sheave 8i .is rotatably mounted in a housing 89 formed integral with a 'support 98 of the same construction as the support 83 and disposed -between the lowermost and intermediate bars 23. Similarly, bearings'Sl and 92 surround, respectively, the lower hub 88 and an upper hub 93 in the intermediate bar 23 to rotatably mount the support 98 between the bars. The hub 93 iscommon to the upper and lower ends, respectively, of the supports 98 and 901i.

The cable 19 as extended from the bottom of' the drum 21 passes under the sheave 88, then upwardly through the Support 83 and hub 88, and finally over the sheave 8|. The housings 82 and 89are constructed to aid in confining the cable on the sheaves, but as a further aid the supports are provided with projections 91|.V

It'is characteristic of the two supports 83 and 98 that they are vertically alined so that the two sheaves revolve about the same vertical axis. By this manner of mounting the sheaves the sheave 88 is free to assume the positions necesv sary to cause proper spiral winding of the cable project from the housing to on the drum, while the sheave 8| can revolve through an angle of 180 degrees to maintain a fair lead of the cable in respect to any mechanism or devices to which it is attached. It is important to note that the stretch of cable between the sheaves is coaxial with the axis of the supports so that there will be no lateral displacement of the cable and in order that a yfair lead will be maintained in any angular position of adjustment of either support.

Referring now to Figs. '7, 8, and 11, the gears -48 for the drums 21 are positively driven `by a mechanism which is characterized by parts capable of being interchanged to compensate for variation in both direction and rotational speed of the transmission shaft of the tractor from which mower is taken to propel the mechanism. Thus, the rotational speed of the Winchdrums and resultant linear speed of the cables can be made constant to operate the devices to be pulled or The invention also includes a power take-off mechanism and a mounting means therefor which permit such mechanism to be applied yto the transmission shaft of any conventional form of tractor and driven thereby to, in turn, actuate the driving mechanism for the winch drums.

'I'he driving mechanism'is situated at the for- -ward side of the winch housings to permit of its being operatively connected to the power take-olf mechanism mounted on the rear endof the tractor. As shown in Fig. 1l, this driving mechanism comprises a countershaft 95 on the ends of which are gears 96 meshing with the respective gears 48. 'I-he gears 96 are contained within the lower housing H with the shaft disposed exteriorly thereof where it extends between bearings 91 secured to the housing. A third gear98 is fixed on the shaft 95 to mesh with a similar gear 98a xed on a jack shaft 99` journaled in suitable bearings contained-in a housing |88 bolted to the housing H. The ends of the shaft 99, which project from the housing |88, are'screw-threaded to receive and secure to either shaft end a double sprocket wheel |8|. Over this sprocket wheel is trained a double sprocket chain |82 for connec-l part of the power take-off mechanism. As J shown in Figs. 1-1 and 1 2, this mechanism comprises a driven shaft |84 journaled in two bearings |85 secured, respectively in collars |86 on the inner sides of two end plates |81 and |88. TheseV plates are removably secured to and constitute th ends of a housing |89 for the shaft |84 except where the latter extends through the plate |81 to permit attachment of a sprocket wheel |83.

For securing the housing |89 to the rear wall ||8 of the tractor shown in Fig. 1, a plate is bolted to the housing and to the tractor Wall, as shown in Fig. 12., This-plate is constructed to permit extension therethrough of a driving shaft ||2 operatively connected to `the shaft |84 by beveled gears ||3 and ||4. A pocket I5 in the plate receives suitable bearings ||6 for the shaft, and this pocket is closed by a cover plate |1 bolted to the plate andv which is designedto snugly fit within the usua-l opening provided in the wall ||8.

From the co'ver plate the shaft ||2 projects through the tractor wall for connection by an I upper adapter shaft IIS to the rear end of the transmission shaft I2|lof the tractor. As shown in Fig. 12, the shaft' I I9 is connected to the shafts |I2 and |20 by splined joints I2I.

By detaching the plates lill-|08 from the housing it is possible to reverse the position of the shaft |04 with respect to the shaft |I2, as indicated in dash lines in Fig. 12. Such shaft reversal positions the sprocket wheel |03 to the opposite side of the housing to place the gear I |3 again in mesh with the gear ||4. Thus, if the transmission shaft is rotating in the opposite direction to that necessary to drive the drums 21 and 28 in a clockwise direction as when viewed in Fig. 11, then by reversing the shaft |04 as described, proper directional driving of the drums can still be obtained. `-It will of course be understood that mounting the wheel |0I and chain |02 on the other end of the shaft 99 is alsoA necessary to this accomplishment.

It is desirable to drive the winch drums at a speed suiliciently low to effect safe operation of the devices which the cables actuate. Rotational speed of the tractor transmission shafts naturally vary, and to compensate for such variation in a manner to rotate the drums at a preselected safe speed the wheels I0| and |03 can be replaced by larger or smaller wheels as the case may demand to drive the jack shaft 99 at that speed necessary to rotate the drums at the preselected speed.

The entire winch structure and its accompanying driving mechanism can be attached to the rear tractor Wall IIO in the elevated position illustrated in Fig. l, by means oi an attaching support characterized by its adaptability to the.

rear wall of any conventional form of tractor. As best shown in Fig. 13, this support comprises a pair of brackets |22 Vhaving lower ends formed with pads |23 bolted to the tractor wall I I0, and ends formed with ears |24 in which the ends of a tubular cross bar |25 are snugly received. b Another pair of brackets |26 have ears |21 ref ceiving the bar |25, and these brackets are curved rearwardly and secured by bolts |28 (Fig. '7) to' the flat bar 22. Asingle bracket |29 is secured at its lower end to the tractor wall/I I0 by bolts |30, and at its'upper end to the bar 20 by bolts |3I. This bracket |29 is disposed midway between thebrackets I22 and |26.so that it coacts therewith in rigidly supporting the. entire winch in xed position on the rear Wall of the tractor.

Although the invention has been thus far described as comprising two winch units, it will be manifest from the relationship and'construction of the two units that the upper unit and its appurtenances can be removed completely from the lowerunit without aifecting operation of the latter, and thus the winch is reduced to a single unit. To cover the open top of the housing H a.

plate |32 (Fig. 2) is provided having at its forward edge an upstanding flange |33 braced along its length by integral webs |34.

With removal of the upper housing H1, it is'necessary to remove theflat bar 22 with the levers 54 and 54Il and remount the levers 5I on the flange |33. Also, the brackets I22 of the attaching support have to be rebolted to the flange |33.

In Fig. 2 the sheaves for the cables are shown reversely disposed or inverted from the position shown in Fig. 1 for the purpose of elevating the lower sheave 8| to provide ample clearance for the draw-bar (not shown) of a tractor where such bar is at a relatively high elevation.r

the gear to the respective drum;

From the preceding description of my invention taken in conjunction with the accompanying drawings, it will be manifest that I have provided a winch characterized by the relationship and detachability of certain of its parts to form a single or double winch unit, and whereby two or four winch drums are provided to permit operation at a distance of as many devices by their respective cables; and the identity and resultant interchangeability of its parts to simplify manufacture and facilitate assembly thereof.

My invention is characterized also by its adaptability to any conventional form of tractor to utilize the tractor for actuating the winch drums;

placing the complete operation of each winch drum Wholly within control of the operator of the tractor through the clutch and brake mechanlsms provided; and maintaining at all times a fair lead of all cable irrespective of the angular relation of the winch drums or sheaves with respect to the devices operated by the cables.

I claim:

1. A winch, comprising; a housing having end sections and an intermediate section spaced from the end sections; a frame for fixedly securing the sections together; a shaft within the housing, spanning the sections and fixed to the intermediate section against rotation; and drums so journled on the shaft as to, be exposed between the housing sections, said end sections each being in. two parts one detachable from the other to permit the shaft and drums to be inserted or withdrawn from the housing through the end sections.

2. In a winch; a housing; -a shaft fixed therein; a drumjournaled on the shaft; a clutch member fixed on the drum; a ysleeve splined on the shaft; a gear journaled on the sleeve; a second clutch member fixed to the gear; driving means for the gear; and an element rotatable in the housing and having a screw-threaded connection with the sleeve so that by rotation of the element the sleeve will vbe moved to cause the clutch member carried by the gearto engage or disengage the other clutch member according as the element is rotated in one direction or the other.

3. In a winch; a shaft fixed therein; a drum journaled on the shaft; a clutch member flxed on the drum; 'a sleeve splined on the shaft; 'spaced collars fixed on the sleeve; a gear having a hub journaled on the sleeve and embraced by said collars; a second clutch member fixed to the gear and means mounted in the housing and operatively connected to the sleeve for so moving the latter on the shaft as to cause the collars to actuate the gear to move the second clutch member into and out of engagement with the rst mentioned clutch member.

,4. A winch, comprising; two winch units including a pair of housings superposed, detachably secured one to the other, and the confronting sides of which are open; a pair of rotatable drums in each housing; gears, one for each of the drums normally disconnected therefrom and so arranged that the gears for the upper drums mesh with the gears for the lower drums; means for driving the gears f or the lower drums; clutches, one for each of the gears for operatively connecting brakes, one for each of the drums; and actuating mechanisms, one for each clutch and its companion brake by which rotation of the respective drum can be controlled.

5. A winch, comprising; a pair of drums; means for rotatably supporting the drums in end to end i meshing respectively with the 3,103,341 l relation; two gears one for each of the drums;

a shaftv having a-pair of gears Vfixedthereon and I4i'lrst mentioned gears;'a third gear lfixed on the, shaft; a second shaft having a gear fixed thereon and meshing with 1 the third gear; a driven sprocket wheel;

coacting means onthe second shaft and sprocket wheelby which the latter can be secured to either end of the second shaft; a driven shaft substantially parallel toL the' second shaft; a Support for the driven shaft having parts so reversible as to permit reversing 'in position of the shaft in the support; a drivingsprocket wheel fixed on one end'of the driven-shaft so that by reversing the shafts position inthe support the position` of the 'sprocket wheel will be reversed likewise to correspond with a reversal in 'end position on the second shaft of the Adrivensprocket wheel; a chain operatively connecting the two sprocket wheels; a driving shaft; and gears so operatively connecting the driving and driven shafts that Ithe driven shaft, is rotated by the driving shaftl irrespective of its vposition in the support. p l v 6. In combination; a substantially vertical wall; a winch'containing housing; a pair of brackets secured to said Wall, extending upwardly thereof and spaced one from the other; a rod extending between and horizontally supported by said brackets; a second pair of' brackets mounted on said rod and secured to said housing; and a bracket secured to said. wall and extending upwardly thereof and'secured to said housing between the second mentioned pair of brackets. 7. In combination; asubstangtially vertical wall;

a winch containing housing; a 4pair of Vbrackets having lower ends secured to `said wall in spaced relation one tothe other; ears on the upper ends .of said -brackets; a rod spanning the brackets [having its ends secured in said ears; a second pair of spaced brackets havingears on one end through which said rodextendsand secured to said housing at the other end; anda single bracket situated midway between and below the v second pair of brackets and secured atone end to said wall and at the other end to said housing.

8. In combination; a winch drum; driving means therefor; a clutch f or connecting the driving meansrto said drum; an actuator for said clutch; an element adapted for releasingv a brake for said drum; and an opera ive connection between said element and actuator comprising a pair of clevlses; anda rod xedly secured to one of the clevises and movably secured r to the other cievis. 9. In combination; a winchdrum; a brake actuating lever; a sprlngconnected to said lever for urging the latter in one direction wherein a \brake is adapted to be applied to the drum; -a member operable to move the lever in the opposite direction wherein the brake is adapted to release the drum; a -driving means for rotating .the winch drum in one direction; a clutch for operatively connectingvthe` driving means to the winchdrum; a clutch operating arm; and a connector between said m and member floractuating .the latter by movement ofv the arm, said arm being pivoted to occupy a neutral position in which the clutch is disengaged and the brake applied, a second position in which the clutch is engaged and the brake free to be released, and a third position in which the clutch is disengaged and the brake released, said connector comprising'at least two. elements, and means for connecting said elements to allow movement of one element with respect to the other before the arm actuates the member so as to delay movement of the member by the arm,

sufficiently to permit complete engagement or applying the brake. f

- A JOHN J. LOW. 

